LONDON, Sept 13 Britain's energy network
operator National Grid stopped a number of wind turbines
in Scotland for a third consecutive night on Monday, the
operator said, as high winds threatened to cause an overload in
power output and block the grid.
"There was some curtailment again last night due to high
wind generation and low demand - 650 MW (megawatts), about 13
wind farms," a spokesman for National Grid said.
On Saturday and Sunday night, 750 MW and 300 MW of wind
capacity was shut down as remnants of hurricane Katia hit the
British mainland, creating wind speeds of 75-80 miles per hour.
When high power output from wind farms, mainly located in
Scotland, coincides with low electricity demand periods at
night, the local transmission network overloads. In these
scenarios National Grid cuts off a number of wind farms to ease
National Grid data showed wind power production reached
around 3,100 MW overnight on Monday, compared with a new record
high of 4,500 MW set last week.
Forecasts for Tuesday and Wednesday were lower, ranging
between 1,000 and 2,500 MW.
Wind turbines generate power at wind speeds of 16 metres per
second (m/s) in the best conditions but shut down when speeds
exceed 26 m/s.
In 2010 wind generation provided 4.2 terawatt-hours of
energy, covering 1.3 percent of UK demand.
(Reporting by Karolin Schaps, editing by Jane Baird)